Shengling Wang; Yong Cui; Das, S.; Mingwei Xu; Communications Workshops, ICC Workshops '08. IEEE International Conference on May 19-23, 2008 Page(s): Presented by Chieh-Yu Tsai, Sep 26,
Outline Introduction Technical Background Proposed Optimized Mobile MPLS and Performance Analysis Simulation Result 2
Optimized Mobile MPLS 3
Introduction Mobile IPv6 is not designed to provide good Quality of Service over dynamic mobile environment. To integrate MIPv6 and MPLS is a method to solve this issue. Furthermore, MPLS can achieve high efficiency compared with conventional IP routing since the labels of MPLS network is short and have fixed length. 4
Introduction In recent years, this topic have been discussed in many papers. Mobile MPLS (MMPLS): R. Zhong, K. T. Chen, C.F. Chun, “Integration of Mobile IP and Multi-Protocol Label switching,” in Conf. Rec, 2001 IEEE Int. Conf. Communications, pp. 2123–2127. Extend Hierarchical MPLS: S. Fowler, S. Zeadally, “Fast Handover over Micro-MPLS-based Wireless Networks,” in Conf. Rec IEEE Int. Symposium, Computers and Communications, pp
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Technical Background MPLS (Multi Protocol Label Switching) MPLS is an efficient encapsulation mechanism Uses “Labels” appended to packets (e.g. IP packets) for transport of data. MPLS packets can run on other layer 2 technologies such as ATM, FR, PPP, POS, Ethernet. 7
Label Header for Packet Media Can be used over Ethernet, 802.3, or PPP links Uses two new Ethertypes/PPP PIDs Contains everything needed at forwarding time One word per label Label = 20 bits COS/EXP = Class of Service, 3 bits S = Bottom of Stack, 1 bit TTL = Time to Live, 8 bits LabelEXPSTTL 8
Encapsulations Label PPP Header Layer 2/L3 Packet PPP Header (Packet over SONET/SDH) Label MAC Header Layer 2/L3 Packet LAN MAC Label Header One or More Labels Appended to the Packet 9
Router Example: Forwarding Packets Data Data Data Data Packets Forwarded Based on IP Address address prefix I/F address prefix I/F address prefix I/F 0 10
MPLS Example: Routing Information In label Address Prefix Out I’face Out label In label Address Prefix Out I’face Out label In label Address Prefix Out I’face 0... Out label 0 You can reach thru me You can reach and thru me Routing Updates (OSPF, EIGRP, …) You can reach thru me 11
MPLS Example: Assigning Labels In label Address Prefix Out I’face Out label In label Address Prefix Out I’face Out label In label 9... Address Prefix Out I’face 0... Out label Use label 7 for Use label 4 for and Use label 5 for Label Distribution Protocol (LDP) (Downstream Allocation) Use label 9 for
MPLS Example: Forwarding Packets In label Address Prefix Out I’face Out label In label Address Prefix Out I’face Out label Data Data Data Data9 In label 9... Address Prefix Out I’face 0... Out label Label Switch Forwards Based on Label 13
MPLS Operation 1a. Existing routing protocols (e.g. OSPF, IS-IS) establish reachability to destination networks 1b. Label Distribution Protocol (LDP) establishes label to destination network mappings 2. Ingress Edge LSR receives packet, performs Layer 3 value-added services, and “labels” packets 3. LSR switches packets using label swapping 4. Edge LSR at egress removes label and delivers packet 14
Abbreviations and Acronyms Label Switching Router (LSR) & Label Edge Router (LER): The routers which support MPLS routing technique. Forward Equivalence Class (FEC): It is a group of IP addresses that are forwarding over the same packet treatment. 15
Abbreviations and Acronyms (Cont.) Label Forwarding Information Base (LFIB): It contents the information for MPLS packets routing over the network. Label Information Base (LIB): It records the labels and its parameters which are used between two MPLS routers routing. 16
Binding Update in Mobile IPv4 17
Binding Update in Mobile IPv6 18
Optimized Mobile MPLS 19
Optimized Mobile MPLS Integrate Mobile IPv6 and MPLS by additional MPLS header to enhance the performance when roaming to a foreign network. By using an additional IPv6 options header ‘MPLS Header’ to transmit LSP setting up message and MIPv6 Binding Update message at a time. 20
Additional MPLS Header MPLS Options Header Format. (TLV Format) REQ: 8-bit unsigned integer specifies the action that the current router receiving the MPLS header requests the next hop to take. FEC: Variable-length field contains one or more FEC elements. (CoAs) 21
Example of Establishing a Unidirectional LSP Label Forwarding Information Base 22
Performance Analysis The latency of setup LSP in MMPLS: D(AR, CN): Distance between AR and CN. λ: Proportional coefficient. n: Nodes. P R : Latency of each node processing LDP signals. 23
Performance Analysis The latency of correspondent registration over MIPv6: D(AR, CN): Distance between AR and CN. η: Proportional coefficient. T wl : Registration signaling forwarding latency on wireless link. P CN : Registration signaling processing latency of CN. 24
Performance Analysis Formula (1) + Formula (2), Handover latency of MMPLS: 25
Performance Analysis In OMMPLS, the process of registration and LSP setup are carried out at the same time. As a result, the latency of OMMPLS is: Therefore, the performance gain is: 26
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Simulation Scenario Dash-dot lines imply the multiple nodes connect between the endpoints(wired, 17 hops). Throughput of wired links: 2Mbps with 5ms delay. Wireless Connection: IEEE with packet size 500 Bytes in CBR. 28
End to End Latency 29
The Latency of Setting Up LSP 30
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Happy Teacher’s Day 36